Forearm elevation impairs local static handgrip endurance likely through reduction in vascular conductance and perfusion pressure: revisiting Rohmert's curve.

Maximal isometric contraction time (MICT) is critical for most motor tasks and depends on skeletal muscle blood flow at < 40% of maximal voluntary strength (MVC). Whether limb work positions associated with reduced perfusion pressure and facilitated vessel compression affect MICT is largely unknown. In 14 healthy young men we therefore assessed bilateral handgrip MICT at 15, 20, 30, 40, and 70% of MVC in horizontal forearm positions of 0.

[From vibration trauma to pharyngeal muscle instability: A self-sustaining pathophysiological process (circulus vitiosus) in obstructive sleep apnea].

Pharyngeal stability is ensured by both anatomical and non-anatomical factors. In addition to the anatomical width, functional factors are also significant in determining the degree of obstruction of the upper airway. The functionality of the pharyngeal muscles depends on an undisturbed sensorimotor system.

[Critical Closing Pressure (Pcrit) and Negative (Subatmospheric) Expiratory Pressure (NEP) for Diagnosis of Pharyngeal Collapsibility in Patients With Obstructive Sleep Apnea (OSA)].

The determination of critical closing pressure (Pcrit) is the diagnostic gold standard for assessing the severity of pharyngeal instability. Pcrit measurements are typically performed during natural nocturnal sleep (NREM Stage 2) in combination with polysomnography. However, determining Pcrit during sleep is time-consuming and impractical for routine use.

An Interdisciplinary Approach: Presentation of the Pediatric Obstructive Sleep Apnea Diagnostic Examination Form (POSADEF).

This report emphasizes the need for interdisciplinary collaboration in diagnosing and treating pediatric obstructive sleep apnea (OSA). OSA, affecting 1% to 4% of children, often results from adenotonsillar hypertrophy, craniofacial disorders, or obesity. While adenotonsillectomy is the primary treatment, about 75% of children, especially those with craniofacial disorders or obesity, continue to experience OSA symptoms post-surgery.

[Valsalva and Müller maneuvers: who is who and what is what?].

The original Valsalva manoeuvre (VM) was described in detail by the Italian anatomist, physician and surgeon Antonio Maria Valsalva (1666-1723). The VM consists of a voluntary forced expiratory effort against a closed upper airway. It was used tradionally in otolaryngology for testing the openess of the eustachian tubes and expelling pus/fluid from the middle to the external ear.

Is sleep bruxism in obstructive sleep apnea only an oral health related problem?

Background: The etiology of sleep bruxism in obstructive sleep apnea (OSA) patients is not yet fully clarified. This prospective clinical study aimed to investigate the connection between probable sleep bruxism, electromyographic muscle tone, and respiratory sleep patterns recorded during polysomnography.

Methods: 106 patients with OSA (74 males, 31 females, mean age: 56.

[The experimental physiologist Carl Ludwig (1816-1895): Scientific genius - modest, selfless, unswerving!].

Carl Ludwig was, besides Johannes Müller, one of the most prolific natural scientists of the 19th century. Carl Ludwig believed that the function of organs can be ascribed to the laws of physics and chemistry and that only through repeatable physiological experiments can hypotheses be verified. Ludwig has laid the technological foundations for experimental physiology.

Optical Genome Mapping as a Potential Routine Clinical Diagnostic Method.

Chromosome analysis (CA) and chromosomal microarray analysis (CMA) have been successfully used to diagnose genetic disorders. However, many conditions remain undiagnosed due to limitations in resolution (CA) and detection of only unbalanced events (CMA). Optical genome mapping (OGM) has the potential to address these limitations by capturing both structural variants (SVs) resulting in copy number changes and balanced rearrangements with high resolution.

[The search for the "node of life": breathing regulation].

The article provides a historical overview of developments in the understanding of respiratory rhythm and its control mechanisms over the last two centuries. In the 19 century, a structure in the medulla oblongata was first described as the "node of life". In 1743, Taube discovered the carotid body, and in 1927 the Spaniard de Castro described its morphology and innervation.

Genome Mapping Nomenclature.

Background: Genome Mapping Technologies (optical and electronic) use ultra-high molecular weight DNA to detect structural variation and have application in constitutional genetic disorders, hematological neoplasms, and solid tumors. Genome mapping can detect balanced and unbalanced structural variation, copy number changes, and haplotypes. The technique is analogous to chromosomal microarray analysis, although genome mapping has the added benefit of being able to detect and ascertain the nature of more abnormalities in a single assay than array, karyotyping, or FISH alone.

Undiagnosed obstructive sleep apnea syndrome as a treatable cause of new-onset sleepiness in some post-COVID patients.

Background And Purpose: Infection with COVID-19 can lead to persistent sequelae, such as fatigue, daytime sleepiness or disturbed sleep, that can remain for more than 12 weeks and that are summarized as post-COVID syndrome. The causes remain unclear. The present study investigated the presence of sleep disorders in patients with post-COVID syndrome using polysomnography.

[From "processing" and "fermentation" to oxidative metabolism].

The theory of the four humors or humorism (Hippocrates of Kos) viewed disease as an imbalance of the humors. Galen of Pergamon further developed the theory by describing digestion as a sequence of chemical reduction processes that convert into the various humours. Theophrastus von Hohenheim attempted to overcome humorism in the 16th century and establish medicine on a natural-philosophical-alchemical basis.

Aneuploidy in oocytes from women of advanced maternal age: analysis of the causal meiotic errors and impact on embryo development.

Study Question: In oocytes of advanced maternal age (AMA) women, what are the mechanisms leading to aneuploidy and what is the association of aneuploidy with embryo development?

Summary Answer: Known chromosome segregation errors such as precocious separation of sister chromatids explained 90.4% of abnormal chromosome copy numbers in polar bodies (PBs), underlying impaired embryo development.

What Is Known Already: Meiotic chromosomal aneuploidies in oocytes correlate with AMA (>35 years) and can affect over half of oocytes in this age group.

[The upper airway in obstructive sleep apnea patients is pathological even when awake].

Obstructive sleep apnea (OSA) is characterized by partial or complete obstruction of the pharyngeal airway. Anatomical factors can be distinguished from non-anatomical factors. Age and obesity are the main risk factors for OSA; however, approximately 50% of patients are not obese.

[Sleep disorders in patients with chronic tinnitus].

Tinnitus has a lifetime prevalence of 25% in Germany. A common comorbidity in chronic cases are sleep disorders. The aims of this study were to detect sleep disorders and to identify possible associations with tinnitus parameters.

[Johannes Müller (1801-1858) and his school: pioneer and giant of German physiology].

Johannes Müller was indisputably the most versatile and brilliant physiologist in the mid-nineteenth century. Müller was born in Koblenz in 1801 as the eldest of five children. He received an excellent education in mathematics and the ancient languages and was thus able to read with ease the writings of Aristotle in the original.

Chronic cough in postmenopausal women and its associations to climacteric symptoms.

Background: Postmenopausal women often have chronic cough. Hormonal changes might be affecting lung function and the mucous membrane of the airways, causing hypersensitivity of the cough reflex. Therefore, postmenopausal hormonal changes could play a key role in the association between increased cough and menopause.

[In commemoration of Adolf Kussmaul's 200th birthday: Describer of the Kussmaul Breathing and pioneer of endoscopy].

Adolf Kussmaul (1822-1902) studied medicine in Heidelberg. The name Kussmaul is known worldwide for the panarteritis nodosa, the pulsus paradoxus and the venous pulse in callous mediastinopericarditis as well as the high-frequency and deep breathing in diabetic ketoacidosis. Kussmaul was also a pioneer in the endoscopic diagnosis and treatment of diseases of the oesophagus and stomach.

[Why you should know the "nose cycle" as a pneumologist and sleep medicine specialist].

The nasal cycle refers to the anticyclic swelling and decongestion of the two nasal cavities that occur during the day and during sleep, while the overall nasal flow remains constant. The nasal cycle was first described by R. Kayser in 1895.

[Analysis of Snoring in Patients with Obstructive Sleep Apnea (OSA) by Polysomnography and LEOSound].

Introduction: Snoring was monitored in patients with obstructive sleep apnea (OSA) using the LEOSound-Monitor and simultaneously polysomnographic (PSG) recording. In obstructive apneas snoring is normally apparent after apnea termination and the beginning of ventilation. We wanted to know how often obstructive apneas are terminated by ventilation in combination with snoring.

[Langhans' or Langerhans' cells? - The problem of the eponym].

There is frequent confusion between Theodor Langhans (1839-1915) and Paul Langerhans (1847-1888) in the literature. Theodor Langhans was a German pathologist who discovered and described the "giant cells" with nuclei close to the outer membrane of the tubercles. Today, these cells are called "Langhans' giant cells".

Acoustic Monitoring of Night-Time Respiratory Symptoms in 14 Patients with Exacerbated COPD Over a 3- Week Period.

Introduction: In clinical practice, wheezing and coughing represent a worsening of the respiratory situation of COPD patients and should be monitored long-term during and after an Acute Exacerbation of COPD (AECOPD) to observe the therapy. We investigated if overnight monitoring of wheezing and coughing is feasible during AECOPD and whether automatic long - term monitoring enables an objective assessment during and after an AECOPD.

Methods: In 14 patients (age: 56-80 years) with pre-existing COPD (stages B-D) nighttime wheezing and coughing events were monitored for a period of three weeks.

[Why the Wittenberg anatomist and scientist Konrad Victor Schneider (1614-1680) is also important for pneumologists].

The Wittenberg physician Konrad Victor Schneider (1614-1680) was the first to prove that mucus is not formed in the brain, nor is it secreted into the nasal cavity via the ethmoid bone. He recognised that there is no open anatomical connection between the brain and the nasal air space. Schneider discovered the sinonasal mucosa as the production site of mucus and thus refuted the hypothesis of cerebral mucus production and secretion by Hippocrates, Galen and Vesal.